Cooking appliance



Aug. 4, 1942. L WOODMAN 2,291,857

' COOKING APPLIANCE Filed Nov. 21, 19 59 2 Sheets-Sheet 1 KENNETH 1.. W000 Q1; ti;

f L f? I 27 A ic U A T Ti WITNESSES 7 g1 a Aug. 4, 1942. K. L. WOODMAN cooxme APPLIANCE 2 Sheets-Sheet 2 Filed Nov. 21, 1959 HIGH MEDIUM Low BROI L TO ROASTER INVENTOR P'atented Aug. 4,1942

COOKING APPLIANCE Kenneth L. Woodman, Mansfield, Ohio, assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application November 21, 1939, Serial No. 305,528

' Claims. (Cl. Mil-37) My invention relates to a cooking appliance, more particularly to a cooking appliance having a heating unit which is adapted to direct heat upwardly for surface cooking and to radiate heat downwardly for broiling, and it has for an object to provide an improved cooking appliance I of the character set forth.

A more particular object is to provide a heating unit of the character set forth and a circuit arrangement therefor which are adapted to provide efiicient heating when used for surface cooking.

In accordance with my invention, 1 provide a heating unit wherein the heat is concentrated within a reduced area of the heating unit when it is used for surface cooking, 50 that the heat may be more effectively utilized by an ordinary cooking vessel of the type used for surface cooking.

These and other objects are effected by my invention as will be apparent from th following description and claims taken in connection with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a front elevation, with parts in section, of a cooking appliance in accordance with my invention;

Fig. 2 is a plan view of the heating unit with the switch and connections indicated diagrammatically;

Fig. 3 is a diagrammatic view of the switch contacts and their connections with the heating elements; and

Figs. 4 to 7 are diagrammatic views showing the circuit arrangements effected by the switch in the high, medium, low, and broil positions, respectively.

Referring to Fig. 1, I show a cooking appliance Ill, in which there is incorporated an electric roaster H and a combination broiler and hotplate l2. This appliance may, therefore, be referred to as a roaster-broiler hotplate. The appliance Ill is provided with electric cord l3 to which there is attached at its outer end a conventional plug it having prongs l5 and adapted to be plugged into any conventional convenient outlet of the type commonly provided in houses wired for electric current. The appliance I0 is, therefore, of the type commonly referred to as a lamp socket appliance, as distinguished from the The roaster ii is incorporated in the righthand half of the body portion it of the appliance it, as indicated in Fig. 1, and is provided with a removable cover if. It is also provided with a suitable switch it, which may be both thermostatically and automatically controlled. In the present embodiment, the current consumption of the roaster is 1650 watts.

The combination broiler and hotplate comprises a heating unit it disposed immediately below and in registry with an opening 2! formed in the top wall or platform 22 of the body portion it. A sliding drawer 23 having a suitable broiling rack N is disposed beneath 'the heating unit to support articles of food to be broiled.

The heating unit i9 includes, as shown in Fig. 2, a frame 25 which comprises bars 26 and 21 extending at right angles and welded to each other to form a skeleton. framework. This frame is adapted to support cooking vessels placed directly thereon, for example, an ordinary frying pan 28.

The heating unit further comprises three electric heating elements A,'B and C. The three heating elements together are distributed over an area suitable for broiling articles of food on the rack 24. The heating elements B and C are arranged in a concentrated portion of that area, which portion is adapted to be'covered by a cooking vessel of ordinary size used for surface cooking, such as the frying pan 28. The three heating elements may be arranged, for example,

in nested relation, as shown in Fig. 2, wherein the intermediate element B extends about three sides of the innermost element 0 and the outermost element A extends about three sides of the intermediate element B.

In the present embodiment, each of th heating elements B and C has a capacity of 825 watts when it is connected directly across the line conductors L1 and L2 incorporated in the cord l3 and the cord is connected to a source of current at 115 volts. The heating element A has 8. capacity of 1237/; watts when so connected.

A switch 34 is provided to control the energi- -zation of the heating elements. This switch conventional electric range which is permanently wired to the source of electric current. The current consumption of an appliance of this type is usually limited to a specified maximum,

which is commonly 1650 watts.

may be of any suitable construction and, by way of example, I have shown a rotary switch comprlsingcam discs 35 to 42 controlling associated switch contacts 35' to 42'. These discs are mounted on a common shaft by which they are rotated in unison to five different positions, which I will term the 011, high, medium, low," and broil positions. The cams on these discs are disposed to provide the desired connectlons ior each position oi the switch, as described hereinafter. I

The contacts 35' are adapted to open the circuit extending through switch It to. the roaster ii whenever the switch 34 is adjusted to any one oi its iour heat positions, in order to avoid exceeding the maximum value oi 1650 watts. The contacts II and 31' control the connection oi the heating element A to the conductors Li and 1a, respectively. Similarly, the contacts 38' and 39' control the element B and the contacts 40' and 4| control the element C. The contacts 42' control the series connection between the elements B and C. The switch 34 is constructed and arranged so that when any heating element is de-energized by the switch, it is isolated irom placedthereuponasarespecificallysetiorthin the appended claims.

What I claim is:

1. A cooking appliance comprising a substantially fiat and horizontally mounted heating device comprising first heating elements and one or more second heating elements distributed both line conductors In and In, thereby eliminat- 7 ing the possibility oi a person obtaining a shock when touching an element as might be the case ii the element were disconnected irom only one line conductor.

In the "01! position oi the switch, all oi the contacts 36' to 42' are open and the elements A, B, and C are disconnected irom both sides oi the line. The contacts 86' are closed to complete the circuit to the switch It, so that the latter may control the supply oi current to the roaster II.

In the high" position, shown in Fig. 3. the

7 contacts I8 to 41' are closed to connect the heating elements B and C across the line conductors in parallel with each other, as represented in Fig. 4. Each oi the elements B and C consumes 825 watts, so that the maximum wattage oi 1650 is concentrated within the two heating elements B and C within the reduced portion oi the unit which is adapted to beused ior suriace cooking. Accordingly, the maximum heat permitted oi the appliance may be concentrated on a vessel placed over such reduced portion.

In the next or medium" position oi the switch, the contacts 40' and 4| are closed to connect the heating element C alone across the line conductors, as represented in Fig. 5, to provide the heat equivalent oi 825 watts. Alternatively, the heating element B may be energized instead oi the element C. r

In the low" position, the contacts 38, 42' and 4| are closed to connect the elements B and C in series to the line conductors, as represented in Fig. 6. The heating elements B and C provide the heat equivalent oi 412% watts.

In the broil" position oi the switch, the heating element A is connected across the line conductors to provide the heating equivalent oi l237 watts. The heating elements B and C are connected in series with each other and across the line conductors in parallel with the heating element A, as indicated in Fig. 7. The elements B and C together consume 412 watts, so that the three together provide the heat equiv. alent oi 1650 watts, the maximum permissible current consumption. In this position oi the switch all three heating elements are energized and providedistributed heat ior broiling articles oi iood placed on the rack 24. Tests have shown that an even temperature distribution can be obtained with this circuit arrangement.

While I have shown my invention in but one iorm, it will be obvious to those skilled-in the art that it is not so limited, but is susceptible oi various changes and modifications without departing irom the spirit thereoi, and I desire, thereiore, that only such limitations shall be throughout the heating area oi the heating device with the first heating elements concentrated in a portionoi said area suitable'ior suriace cooking, means ior supporting a cooking vessel above said first heating elements to be heated by the latter, means ior supporting articles oi iood below said heating device in a manner suitable ior broiling, and switch means for controlling the connection oi said heating elements to a source oi electrical energy, said switch means providing connections such that, in each position oi the switch means, the current drawn by the connected heating element or elements does not exceed a predetermined permissible value which is less than the total current oi the several elements when individually connected to said source, in one position at least a part 01' the first elements draws a reduced current and the second element or elements are energized so that the heating device provides distributed heat throughout the area thereoi ior broiling, and in other positions, currents oi difi'erent values are drawn by at least a part oi the first elements and the second element or elements are not connected. so that the heating device provides difierent heats in a reduced area ior suriace cooking.

2. A cooking appliance comprising a substantially fiat and horizontally mounted heating device comprising two first heating elements and one second heating element, the three heating elements being distributed throughout the heate ing area oi the heating device with the two first heating elements concentrated in a portion oi said area suitable ior suriace cooking, means ior supporting a cooking vessel above said two first heating elements to be heated by the same, means for supporting articles oi iood below said heating device in a manner suitable ior broiling, and switch means ior controlling the connection oi said heating elements to a source oi electrical energy, said switch means providing connections such that, in each-position oi the switch means, the current drawn by the connected heating element or elements does not exceed a predetermined permissible value which is substantially less than the total current oi the several elements when individually connected to said source, in one position both first elements are energized to provide a high heat ior suriace cooking and the second element is not energized, in a second position a first element or elements are energized to provide a reduced heat for suriace cooking and the second element is not energized, and in a third position a first element or elements are energized to provide a heat less than the heat provided by them in the first position and the second element is energized to provide a distributed heat suitable ior broiling.

3. An electrical heating device comprising first and second heating elements disposed in a concentrated portion oi the heating area oi the heating device, and a third heating element disposed in the remaining portion oi said heating area, and switch means ior connecting said heating elements to a pair oi electrical supply conductors constructed and arranged so as, in a first position thereoi, to connect the first and second heating elements in series with each other to said pair of electrical supply. conductors, in a second position to connect said first heating element alone to said conductors, in a third position to connect the first and second heating elements only to said conductors in parallel with each other to provide a maximum heat output, and in a fourth position to connect said first and second heating elements in series to said conductors and to connect said third element to said conductors in parallel with the serially connected first and second elements to provide substantially the same heat output as in the third position. 4. A cooking appliance comprising a substantially fiat and horizontally mounted heating device comprising a first heating portion including at least two heating elements and a second heating portion including at least one electric heating element, the heating elements being distributed throughout the heating area of the heating device with the first heating portion concentrated in a portion of said heating area suitable for surface heating, means for supporting a cooking vessel above said first heating portion to be heated by the same, means for supporting articles of food below said heating device in a manner suitable Ior broiling, and switch means for controlling the connection of said heating elements to a source of electrical energy, said switch means providing connections such that, in each position of the switch means, the current drawn by the connected heating element or elements does not exceed a predetermined permissible value which is substanthilly less than the total current of the several elements when individually connected to said source, in one position the first heating portion is energized to provide a high heat for surface cooking and the second heating portion is not energized, in a second position the first heating portion is energized to provide a reduced heat for surface cooking and the second heating portion is not energized, and in a third position the first heating portion is energized to provide a heat less than the heat provided by it in the first position and the second heating portion is energized to provide a distributed heat suitable for broiling.

5. A cooking appliance comprising a heating device including a first heating portion including at least two electric heating elements and a second heating portion including at least one electric heating element, the heating elements being distributed throughout the area of the heating device with the first heating portion concentrated in a portion of said heating area, and switch means for controlling the connection of said heating elements to a source of electrical energy, said switch means providing connections such that, in each position of the switch means,

the current drawn by the connected heating element or elements does not exceed a predetermined permissible value which is substantially less than the total current of the several elements when individually connected to said source, in a first position the first heating portion is energized to provide a maximum heat output and the second heating portion is not energized, in a second position the first heating portion is energized to provide a reduced heat output and the second heating portion is not energized, and in a third position the first heating portion is energized to provide a heat output less than the heat provided by it in the first position and the second heating portion is energized to provide a distributed heat throughoutsaidheating area, the combined heat'output of said portions in said third position being substantially the same as the heat output in said first position.

KENNETH L. WOODMAN. 

